Physics Division Seminars

Physics Division Seminars bring us speakers on a variety of physics
related subjects. Usually these are held in the Building 6008
large Conference Room, at 3:00 pm on the chosen day, but times
and locations may vary. For more information, contact our seminar
chairman,

Thu., October 16, 2003, at 3:00 p.m.

Why did Germany not produce an atomic bomb in the Second World War?

Harry Lustig, American Physical Society and City College of New York4500N, Wigner Auditorium

The question why the Germans did not achieve an atomic bomb during World War II has been examined and debated in books, articles, and symposia by physicists, historians of science, and journalists for the past half century. Were the reasons for the failure scientific, technological, economic, organizational, or a result of moral reservations? Why had Heisenberg, by war's end, not even succeeded in building a working nuclear reactor? Did he and the other scientists in the "Uranium Project" understand the difference between a bomb and a reactor? Were the German scientists aware of the role of fast neutrons in a bomb? Did they appreciate that the bomb material plutonium 240 could be produced in a uranium reactor? Did Heisenberg or any other scientist in Germany ever calculate the critical mass of uranium or of plutonium to sustain a chain reaction and to produce an explosion? If not was it because they were convinced that for practical reasons a bomb couldn't be assembled in time to be of use to anyone in World War II? If anyone did, was the result a critical mass of tons or of kilograms? These are some of the questions that have been asked and in some cases answered, but the conclusions are often contradictory. I am now examining the most relevant of some 300 declassified German Research Reports, in the hope that the science in them will help settle the issues. My talk will be a preliminary progress report.